The team is still reeling from Jimmy being shot. But, now they have a witness they are hiding from everyone as the SIU team secretly work to solve Jimmy Blue's attempted assassination. Their first case is a mystery wrapped in a riddle as they hunt down a serial killer and sexual predator preying on innocent women. But, they have an even bigger threat looming in the shadows.

Chief Wryles breaks his silence and give us a glimpse into his master plan. But, his world goes sideways when Darius resurfaces and blackmails him. SIU has its hands full with a bizarre murder triangle of a high-end fashion model. Gloria admits a painful secret she's been hiding from Jimmy and Jasmine is battling her own demons as she confronts her feeling about Yolanda.

Tarik and Tessa are becoming leaders in their own right. The crime world is stirring, and SIU finds themselves in the middle of a war. Then, as luck would have it, they get a key piece of information linking Jimmy's shooting to Argon. Tarik and Han go head to head in a battle of wits to find Jimmy's killer and once the dust settles, no one will be the same.

The sins of SIU have come back to haunt them. A team member has been kidnapped by a highly intelligent vigilante. The Vigilante's motives become clear and has been plotting for a long time. As the Vigilante's master plan draws to its conclusion the question becomes will SIU join him in his crusade or will they stop him?

Jimmy is up and about and staying away from SIU. Miriam and Zakia continue to work the case against Argon, but Argon and Han are plotting, and their plans are unfolding. Darius and Argon continue their 'business' partnership with Darius' daughter held as a bargaining chip. The team is falling apart, but through it all they are still SIU.

The team's personal and professional life come crashing together. Argon manipulates SIU to his own ends, while Han plots a bigger goal. Tess and Tarik try to hold down SIU as Yolanda becomes more erratic. She reaches out to Jimmy, only for him to shut her out. Jimmy and Darius finally meet, but it can only end at gun point. No one escapes the disastrous fallout of this episode's season finale.